Urinary Microbiome and its Correlation with Disorders of the Genitourinary System.

PURPOSE: Until recently, the urine of healthy individuals was assumed to be sterile. However, improvement of bacterial detection methods has debunked this assumption. Recent studies have shown that the bladder contains microbiomes, which are not detectable under standard conditions. In this review, we aimed to present an overview of the published literature regarding the relationship between urinary microbiota and functional disorders of the genitourinary system. METHODS: We searched Medline, PubMed, Embase, The Cochrane library and Scopus to identify RCTs published, with MeSH and free keywords including microbiota, bladder pain syndrome, prostatitis, kidney stone disease, and bladder cancer until September 2020. Randomized controlled trials investigating microbiome and lower urinary tract symptoms were included. Non-randomized trials, cross-over trials and pooled studies were excluded. The articles were critically appraised by two reviewers. CONCLUSION: The urine microbiome is a newly introduced concept, which has attracted the attention of medical researchers. Since its recent introduction, researchers have conducted many fruitful studies on this phenomenon, changing our perspective toward the role of bacteria in the urinary tract and our perception of the genitourinary system health. RESULT: A deeper understanding of the urinary microbiome can help us to develop more efficient methods for restoring the microbiota to a healthy composition and providing symptom relief. Modification of the urinary microbiome without antibiotic use can be a possible venue for future research.

Synchronous genitourinary lichen sclerosus signals a distinct urinary microbiome profile in men with urethral stricture disease.

PURPOSE: Alterations in the urinary microbiome have been associated with urological diseases. The microbiome of patients with urethral stricture disease (USD) remains unknown. Our objective is to examine the microbiome of USD with a focus on inflammatory USD caused by lichen sclerosus (LS). METHODS: We collected mid-stream urine samples from men with LS-USD (cases; n = 22) and non-LS USD (controls; n = 76). DNA extraction, PCR amplification of the V4 hypervariable region of the 16S rRNA gene, and sequencing was done on the samples. Operational taxonomic units (OTUs) were defined using a > 97% sequence similarity threshold. Alpha diversity measurements of diversity, including microbiome richness (number of different OTUs) and evenness (distribution of OTUs) were calculated and compared. Microbiome beta diversity (difference between microbial communities) relationships with cases and controls were also assessed. RESULTS: Fifty specimens (13 cases and 37 controls) produced a 16S rRNA amplicon. Mean sample richness was 25.9 vs. 16.8 (p = 0.076) for LS-USD vs. non-LS USD, respectively. LS-USD had a unique profile of bacteria by taxonomic order including Bacillales, Bacteroidales and Pasteurellales enriched urine. The beta variation of observed bacterial communities was best explained by the richness. CONCLUSIONS: Men with LS-USD may have a unique microbiologic richness, specifically inclusive of Bacillales, Bacteroidales and Pasteurellales enriched urine compared to those with non-LS USD. Further work will be required to elucidate the clinical relevance of these variations in the urinary microbiome.

Rigorous characterization of urinary extracellular vesicles (uEVs) in the low centrifugation pellet - a neglected source for uEVs.

Urinary extracellular vesicles (uEVs) provide bio-markers for kidney and urogenital diseases. Centrifugation is the most common method used to enrich uEVs. However, a majority of studies to date have focused on the ultracentrifugation pellet, potentially losing a novel source of important biomarkers that could be obtained at lower centrifugation. Thus, the aim of this study is to rigorously characterize for the first time uEVs in the low speed pellet and determine the minimal volume of urine required for proteomic analysis (≥9.0 mL urine) and gene ontology classification identified 75% of the protein as extracellular exosomes. Cryo-Transmission Electron Microscopy (≥3.0 mL urine) provided evidence of a heterogeneous population of EVs for size and morphology independent of uromodulin filaments. Western blot detected several specific uEV kidney and EV markers (≥4.5 mL urine per lane). microRNAs quantification by qPCR was possible with urine volume as low as 0.5 mL. Particle enumeration with tunable resistive pulse sensing, nano particles tracking analysis and single EV high throughput imaging flow cytometry are possible starting from 0.5 and 3.0 mL of urine respectively. This work characterizes a neglected source of uEVs and provides guidance with regard to volume of urine necessary to carry out multi-omic studies and reveals novel aspects of uEV analysis such as autofluorescence of podocyte origin.

Urine proteomics in kidney and urogenital diseases: Moving towards clinical applications.

To date, multiple biomarker discovery studies in urine have been conducted. Nevertheless, the rate of progression of these biomarkers to qualification and even more clinical application is extremely low. The scope of this article is to provide an overview of main clinically relevant proteomic findings from urine focusing on kidney diseases, bladder and prostate cancers. In addition, approaches for promoting the use of urine in clinical proteomics including potential means to facilitate the validation of existing promising findings (biomarker candidates identified from previous studies) and to increase the chances for success for the identification of new biomarkers are discussed.

Population-based outreach for Chlamydia screening in men: results from a randomized trial.

OBJECTIVE: To evaluate the feasibility and efficacy of population-based outreach strategies to improve genital Chlamydia trachomatis (CT) screening in men. STUDY DESIGN: In a randomized trial, male enrollees ages 21-25 (n = 8820) were selected from the automated files of Group Health Cooperative and randomized to: a letter + test-request card for a CT urine home sampling kit (arm 1, n = 2940); a letter + mail-back sampling kit (arm 2, n = 2940); or a usual care control (arm 3, n = 2940). One reminder was sent to arms 1 and 2. The outcome was CT testing rates in the 4 months postrandomization. RESULTS: 105 of 2940 (3.6%) men in arm 1 and 230 of 2940 (7.8%) in arm 2 returned mailed specimens. All 335 respondents were sexually experienced, 43% had >2 sex partners in the past year, and 80% reported no genitourinary symptoms. Compared to arm 3, the relative risk of being tested was 5.6 (95% confidence interval (CI) 3.6-8.7) for arm 1 and 11.1 (95% CI 7.3-16.9) for arm 2. Arm 2 was significantly more likely to be tested than arm 1. CT prevalence for mailed-back specimens was 1.0% (1 of 105) for arm 1 and 2.6% (6 of 230) for arm 2; 70% of all positive intervention tests were from mailed samples. CONCLUSIONS: Both strategies resulted in significantly higher CT testing than usual care, but the intervention response rate was low (5.7% overall). Direct kit mailing performed best. In US populations, the value of mailed outreach strategies to men must be considered in the context of other CT screening priorities.

Mailed urine samples are not an effective screening approach for Chlamydia trachomatis case finding among young men.

BACKGROUND: Frequency of testing is known to be low for sexually transmitted infections (STIs) in men aged 20-24 years. The use of mailed, home-obtained urine specimens could increase the uptake of young men and facilitate screening programmes for the detection of asymptomatic Chlamydia trachomatis. OBJECTIVE: The aim of the present study is to evaluate the home screening approach as a tool for recruitment of asymptomatic men for screening of genital C. trachomatis infections. METHODS: Men aged 19-24 years old (n = 1936) were invited to participate in home-based testing for genital C. trachomatis infection. Persons who agreed to be tested were provided with a testing kit. Self-collected first void urine was sent for testing to the microbiology laboratory. The test result was accessible on the study's web-page 1 week after testing. Individuals with a diagnosed infection were instructed to contact the venereal disease department. RESULTS: The response rate was 24% (462/1936). The responders' main reason for not participating was a feeling of being safe regarding STIs (87%; 159/182). The primary reason for this feeling of safety was that the responders were in a steady relationship (59%; 107/159). Having sex outside a steady relationship was reported by 36% (90/250) of the responders. The prevalence of C. trachomatis infection among the responders was 2.02% and the reported history of chlamydial infection was 36% (34/95). Out of the responders, 92% (229/249) were, to varying degrees, concerned about getting STIs; however, the majority (72%; 174/242) estimated the risk to be low. CONCLUSION: Home screening using web-based answer management is a feasible tool for STI screening, which lowers the threshold for people at risk. In this particular population, however, the response rate was too low to be routinely introduced.

Identification of novel risks for nonulcerative sexually transmitted infections among young men in Kisumu, Kenya.

OBJECTIVES: STI prevention interventions often aim to reduce HIV incidence. Understanding STI risks may lead to more effective HIV prevention. GOAL: To identify STI risks among men aged 18-24 in Kisumu, Kenya. STUDY DESIGN: We analyzed baseline data from a randomized trial of male circumcision. Participants were interviewed for sociodemographic and behavioral risks. Neisseria gonorrhoeae (NG) and Chlamydia trachomatis (CT) were diagnosed by polymerase chain reaction assay and Trichomonas vaginalis (TV) by culture. The outcome for logistic regression analysis was infection with NG, CT, or TV. RESULTS: Among 2743 men, 214 (7.8%; 95% CI: 6.8%-8.8%) were infected with any STI. In multivariable analysis, statistically significant risks for infection were: living one's whole life in Kisumu (OR = 1.50; 95% CI: 1.12-2.01), preferring "dry" sex (OR = 1.47; 95% CI: 1.05-2.07), HSV-2 seropositivity (OR = 1.37; 95% CI: 1.01-1.86), and inability to ejaculate during sex (OR = 2.04; 95% CI: 1.15-3.62). Risk decreased with increasing age and education, and cleaning one's penis less than 1 hour after sex (OR = 0.51; 95% CI: 0.33-0.80). CONCLUSION: Understanding how postcoital cleaning, "dry" sex, and sexual dysfunction relate to STI acquisition may improve STI and HIV prevention.

Use of quantitative real-time PCR to monitor the shedding and treatment of chlamydiae in the koala (Phascolarctos cinereus).

The aim of this study was to monitor chlamydial shedding patterns in clinically affected koalas before, during and following treatment using quantitative real-time PCR. Swab samples were obtained from 14 koalas presented for treatment at the Australian Wildlife Hospital. Four of these animals were followed over a period of 8-9 weeks. Primers were designed based on the consensus signature sequence of the 16S rRNA chlamydial gene. Additional primers were designed based on the sequence of the koala beta-actin gene and used to normalize chlamydial values when comparing results from different swab samples. Chlamydial 16S rRNA gene copy number was highest in swab samples from clinically affected sites. Daily injections of chloramphenicol resulted in a marked and rapid reduction in the numbers of chlamydiae being shed from all sites. In general, chlamydial copy number was no longer detectable by the end of the 2nd week of treatment. No evidence of relapse of infection was detected at 2 weeks after the cessation of treatment. In contrast, topical chloramphenicol treatment of the eyes required a longer treatment period and had little effect on the shedding of chlamydiae from other sites of the body. Further studies are required to confirm the efficacy of a shorter treatment period.

[Detection of Chlamydia trachomatis infection by PCR in first voided urines in men]. / Détection d'une infection masculine à Chlamydia trachomatis par PCR sur premier jet d'urine.

The goal of this study was to evaluate whether the new commercially available PCR-based assay Amplicor C. trachomatis (Roche Molecular Systems) could improve the diagnosis of chlamydial urogenital infections in men, compared with cell culture of C. trachomatis considered as the reference method. A total of 466 men attending the STD clinic were tested by the Amplicor test in urine and by cell culture in urethra. The prevalence of C. trachomatis was 13.7% (64/466) by cell culture and 14.4% (67/466) by the Amplicor test. After resolution of the discrepant results, the sensitivity of culture was 91.4% in male urethral specimens. The resolved sensitivity of the PCR assay was 92.7% in male urine and the specificity was 99.5%. We concluded that this rapid PCR-based assay showed an improvement in quality for diagnosing C. trachomatis infections in men.